Instrument guide for use with needles and catheters

ABSTRACT

A guide is provided for use with an imaging instrument, the guide including a first portion, a second portion proximate the first portion, and a cavity at least partially formed by the first and second portions, the cavity having a cavity width and configured to retain an instrument therein. The cavity width is selectively changeable to accommodate a plurality of diameters by sliding the second portion along a path with respect to the first portion.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of and claims the benefit under 35U.S.C. §121 of application Ser. No. 10/961,936, filed on Oct. 8, 2004,now issued as U.S. Pat. No. 7,909,815, which in turn claims the benefitunder 35 U.S.C. §121 of Continuation-in-Part application Ser. No.10/851,030, filed May 21, 2004, now abandoned, which in turn claims thebenefit under 35 U.S.C. §119(e) of Provisional Patent Application No.60/472,749, filed on May 23, 2003, the contents all of which areincorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to a guide for use with a medical imaginginstrument. More particularly, the invention relates to a guide systemfor use in guiding elongate medical instruments into selected locationsof a patient's body relative to an imaging sensor.

BACKGROUND OF THE INVENTION

Medical imaging often is conducted in tandem with the insertion of aneedle, catheter, or other instrument into a subject in order to obtaina biopsy sample or perform an image-assisted medical procedure. Forexample, it has become increasingly accepted to perform standardradiography, fluoroscopy, ultrasound, computed tomography (CT) scanning,and magnetic resonance (MR) imaging while a medical instrument is beingpositioned and/or operated. In order for the imaging to be useful, it isimportant to provide a known alignment between the imager and medicalinstrument. Although it is possible to perform image-assisted medicalprocedures by positioning an instrument visually using an iterativeprocess in which the instrument's trajectory is adjusted followinginspection of successive images showing the instrument's position, sucha technique is inefficient, slow, cumbersome and suffers from high riskassociated with initial improper alignment.

For example, ultrasound is known to have use in real time needleguidance, enabling accurate targeting of internal structures duringinterventional procedures such as biopsy, drainage or focal therapiesthat can be delivered through a needle or small diameter probe. Thereare two fundamental techniques for ultrasound guided needle placement.One approach is known as the “freehand method,” in which an ultrasoundimaging transducer and needle are not coupled and thus are independentlymovable throughout a procedure. In this method, the needle and path to atarget organ are visualized by a skilled operator who holds thetransducer in one hand while advancing the needle with the other. Thecoordination and visual and spatial orientation skills required tosimultaneously maintain the image plane in line with the needle, keepthe target in view, maintain orientation to surrounding structures andmanipulate the needle are substantial and demanding. Thus, the techniqueis not suitable for, or favored by everyone, and there is a steep andprolonged learning curve. The main advantage of the freehand method isthe complete versatility allowed by total freedom of movement of bothneedle and ultrasound imaging transducer.

An alternate approach is known as the “needle guide method,” in which aneedle guide having a known orientation to the ultrasound imagingtransducer is used. Such guides may be integral with the transducer, orinstead may be separate, attachable accessories, and have been made aseither reusable or single-use, sterile, disposable products. In theneedle guide method, the guides are designed to keep any needle passingthrough them on a known path in the image plane, and thus avoid many ofthe difficulties inherent in the freehand technique. Typically, softwareis supplied by the ultrasound equipment manufacturer showing a virtualguide path and depth index on a real time image.

The needle guide method is less reliant on user intuition, skills andexperience and has a shorter learning curve, but has several limitationsthat have hampered universal acceptance. First, the freehand methodpermits the operator to choose any size needle without restriction,whereas the needle guide method typically has required a close tolerancepath for each size needle to work properly. Because of this requirement,manufacturers of prior art needle guides have devised methods thattypically either require significant manipulation of the guide ormultiple parts to permit a range of needle sizes to be accommodatedwithin their guides.

Second, the freehand method permits the operator to have completefreedom of choice for entry site of the needle and angle of attack tothe target, whereas the needle guide method is generally morerestricting, with prior art devices typically offering only a singleangle of attack in relation to the ultrasound transducer. To addressthis restriction, some re-usable needle guides have been designed tooffer up to three different angles of attack, but such devices haverequired significant manual manipulation and have been consideredcumbersome by some users.

Third, when using the needle guide method the needle often must bedecoupled from the guide to continue some procedures, inevitablyrequiring additional and sometimes awkward, time consuming steps. On theother hand, the freehand method permits the operator complete freedomwith the needle once it is in the desired location because the needlemovement is not governed or otherwise restricted by a guide.

Fourth, the needle guide method introduces additional problemsincluding: the requirement for a secure attachment to the transducerthat does not interfere with transducer function, the possiblerequirement for added needle length (to allow for the length of theguide), and the issue of “dead, space” that can exist between the exitof the needle tip from the guide and the entry into the skin which maycontribute to misdirection of the needle. There also may be added coststo the user, although such costs may be balanced by the need for a lessexperienced operator and fewer complications for the patient.

To avoid some of the aforementioned disadvantages as described above,various devices are known for use in guiding medical instruments.

For example, U.S. Pat. No. 6,203,499 B1 to Imling et al. is directed toa multiple angle needle guide comprised of a body that has a slotpositioned between opposing sides. The slot creates a triangular shapedgap between the opposing sides spanning a range of 45° for inclinationof a needle. With this device, the angle of attack in the image plane isnot fixed to a known previously determined path or paths, nor is theneedle fully engaged in the guide but instead free floating in the slot.Also, the slot is not adjustable in width and therefore is only usefulfor a limited range of needle sizes.

U.S. Pat. No. 5,031,634 to Simon is directed to an adjustable biopsyneedle-guide device that can be used to direct a variety of separateaspiration biopsy needles or tissue cutting biopsy needles to a targetlesion. Sets of aligned holes are provided in a handle to aim andcontrol the depth of the needles, with different hole sizesaccommodating various needle gauges. In some applications, the requiredangle of insertion is guided by a goniometer or protractor, or the guideis supported by an adjustable stereotactic device attached to thepatient's skin or a table top. The patent also states that iffluoroscopy is the selected imaging modality, a plastic side-armattachment can be used to hold the handle of the device while it isbeing aimed or advanced into the tissues.

U.S. Pat. No. 5,052,396 to Wedel et al. is directed to a needle guidefor ultrasound transducers having a means for coupling with a transducerand a multi-slotted, removable insert for receiving and guiding needlesof various gauges. The configuration of the transducer, needle guide,needle, and the patient are such that a physician can firmly grasp thetransducer and needle guide with one hand while maintaining contact withthe patient, and manipulate the needle with the other hand.

In addition, U.S. Pat. No. 5,100,387 to Ng is directed to a disposableuniversal needle guide apparatus for amniocentesis. The needle guideapparatus includes a substantially horizontal base to be applied to asurface on or adjacent a zone to be punctured by a needle, an uprightguide flange mounted on the base, and pivot structure associated withthe flange and base. An elongated, tubular guide structure carried bythe pivot structure is manually pivoted and receives the needle forguiding movement thereof at an angle determined by selective swinging ofthe tubular guide structure relative to the base.

Also, U.S. Pat. No. 5,941,889 to Cermak is directed to a multiple angledisposable needle guide system that includes a bracket, a mounting base,a pivoting portion of the mounting base, and a needle guide. The bracketis used to secure the needle guide system to an imaging instrument, suchas an ultrasonic probe. The mounting base is secured to the imaginginstrument by the bracket. The pivoting portion of the mounting base isconfigured to pivot along at least one axis, and the disposable needleguide is removably secured to the pivoting portion of the mounting base.The needle guide has a needle retainer member configured to retain aneedle by application of a clamping force. A plurality ofinterchangeable needle retainer members are used so as to permit needlesof various sizes to be used.

Despite these developments, there remains a need for an improvedinstrument guide that accommodates elongate instruments of differentdiameters without requiring cumbersome adjustments. There furtherremains a need for a guide that permits an instrument to be easilyinserted and removed therefrom, particularly while the instrument (suchas a needle or catheter) is in the patient. For example, it is knownthat with prior art instrument guides the instrument rotates orundergoes undesirable lateral movement during insertion and removal froma patient. Such lateral (sideways) movement preferably are minimized inorder to avoid unnecessary patient discomfort and even trauma, whilepermitting axial movement into and out of the patient. Additionally,there remains a need for an instrument guide with a wide range ofadjustment to accommodate different gauges of instruments.

SUMMARY OF THE INVENTION

The invention relates to a medical instrument guide including a guidebody and a quick-release lever having a support portion, a gaugeindicator portion, and a detent. An insert may be demountably coupled tothe quick-release lever and has a plurality of notches shaped forselective engagement with said detent. The guide body and insert areconfigured and dimensioned to cooperate to form an instrument-receivingchannel and the detent is positioned to index a plurality of differentsizes of the channel. In some embodiments, the guide body andquick-release lever are pivotably coupled to each other. The guide bodymay have a socket and the quick-release lever may have a post, with thepost being accommodated in the socket. Also, the post may demountablysnap-fit in the socket.

The quick-release lever may include a pair of rails and the insert mayhave a pair of insert grooves, with each rail being received in one ofthe insert grooves. The insert may have a locking portion extending froma side thereof, wherein the locking portion may be received in a guidegroove in the guide body. Further, the locking portion may releasablysnap-fit in the guide groove.

The guide body may have at least one stop for limiting travel of thelocking portion in the guide groove. The rails may be aligned with theguide groove when the locking portion is received in the guide groove.

In an exemplary preferred embodiment, the instrument-receiving channelmay define a plurality of central instrument axes corresponding to eachof the indexed sizes, and the insert may travel at an angle transverseto the central instrument axes. Also, an indicator may be visiblethrough a slot in the insert, wherein the indicator and the detentsimultaneously index the same size.

The instrument-receiving channel formed by the guide body and insert mayfor example accommodate elongate instruments with gauge sizes 11 through15, or may for example accommodate elongate instruments with gauge sizes16 through 22. Each of the gauge sizes may be indexed by engagement ofthe detent with a notch. Each insert may further include indiciacorresponding to the indexed gauge sizes.

A lock may be demountably attached to the guide body, wherein the lockand guide body together define an unlocked position and a lockedposition. The lock may include a protrusion, and in the locked positionthe protrusion may extend into a bracket-receiving channel in the guidebody. The medical instrument guide may have a lock operable between anunlocked position and a locked position, wherein in the locked positiona portion of the lock extends into a channel in the guide body.

A bracket also may be provided, wherein the bracket is demountablyattachable to the guide body and secured thereto when a portion of thebracket is disposed in the bracket-receiving channel and the lock isdisposed in the locked position. The bracket optionally may beconfigured and dimensioned to support an ultrasound transducer.

In a preferred exemplary embodiment, the quick-release lever and insertmay be slidably associated with each other. In some embodiments, theguide body and quick-release lever may be integrally formed. Inaddition, the instrument-receiving channel may have a funnel portion.

The invention also relates to a medical instrument guide including afirst portion, and including a second portion having a lever, a gaugeindicator, and a detent. The guide may further include a third portiondemountably coupled to the second portion and having a plurality ofnotches shaped for selective engagement with said detent. The first andsecond portions may be pivotably associated with each other, the firstand third portions may be configured and dimensioned to cooperate toform an instrument-receiving channel, and the detent may be positionedto index a plurality of different sizes of the channel. Theinstrument-receiving channel may be configured and dimensioned toaccommodate a needle or a catheter. A method of guiding an elongatemedical instrument into tissue may include inserting the elongatemedical instrument in the instrument-receiving channel of the medicalinstrument guide. The second portion may be pivotable with respect tothe first portion using one hand of a user. Also, the second portion maybe pivotable with respect to the first portion without substantialmovement of the elongate medical instrument in the instrument-receivingchannel. Further, the instrument-receiving channel may define a centralaxis along which the elongate medical instrument is guided, and whereinthe second portion may be pivotable with respect to the first portionwithout substantial movement of the elongate medical instrument awayfrom the central axis. The elongate medical instrument may be a needleor a catheter. Further, the elongate medical instrument may beconfigured to aspirate a material, heat the tissue, cool the tissue,emit microwaves, or emit radio waves.

The invention further relates to an instrument guide kit for guidingmedical instruments. The kit includes a guide body and a pair of insertseach releasably engageable with the guide body. A combination of theguide body and any one of the inserts may be configured and dimensionedto form an instrument-receiving channel, and each insert may index aplurality of discrete sizes of the instrument-receiving channel.

In addition, the invention relates to a guide for use with an imaginginstrument, the guide including a first portion and a second portionproximate the first portion. A cavity may be at least partially formedby the first and second portions, the cavity having a cavity width andbeing configured to retain an elongate instrument therein. The cavitywidth may be selectively changeable to accommodate a plurality ofdiameters by sliding the second portion along a path with respect to thefirst portion. The second portion may be slidably associated with thefirst portion along a substantially linear path, and the cavity widthmay be adjustable without rotation of the second portion. The secondportion may be slidable at an acute angle with respect to a central axisof the cavity, and the second portion may have an instrument-contactingsurface configured to remain parallel to the central axis. Moreover, thefirst and second portions may be pivotable with respect to each other,and rotation of the second portion may permit generally lateral removalof an instrument from the guide without moving the instrument along thecentral axis. A method of guiding a elongate instrument into tissue mayinclude inserting the elongate instrument in the cavity of the guide.The second portion may be rotatable with respect to the first portionusing one hand of a user. Also, the second portion may be rotatable withrespect to the first portion without substantial movement of theelongate medical instrument in the cavity. In addition, the cavity maydefine a central axis along which the elongate medical instrument isguided, and wherein the second portion may be rotatable with respect tothe first portion without substantial movement of the elongate medicalinstrument away from the central axis. The medical imaging instrumentmay be an ultrasound transducer.

Furthermore, the invention relates to a guide for use with an imaginginstrument, the guide including first and second portions eachconfigured to engage an elongate instrument. An elongate instrument pathmay be defined by the first and second portions, the path having ainstrument path axis. A track may define a travel axis non-parallel tothe instrument path axis, the track configured to engage the secondportion while permitting travel thereof along the track. Travel of thesecond portion along the track permits an elongate instrument diameteraccommodated along the instrument path to change.

The first and second portions may be rotatably associated with eachother, and rotation of the portions with respect to each other maypermit generally lateral removal of the elongate instrument from theguide without moving the elongate instrument along the instrument pathaxis.

The second portion may index a plurality of discrete elongate instrumentdiameters to be accommodated along the instrument path. Also, a bracketmay be provided that is configured and dimensioned for coupling to theimaging instrument, wherein the bracket is demountably associated withthe first portion.

Furthermore, the invention relates to a method of guiding an elongatemedical instrument into tissue comprising: forming a cavity betweenfirst and second portions coupled to each other and rotatable withrespect to each other; sliding the second portion along a path withrespect to the first portion to select a desired cavity dimensionconfigured to receive and guide the elongate medical instrument therein;inserting the elongate medical instrument in the cavity. The method mayfurther comprise at least one of: releasably locking the first andsecond portions to each other, releasably locking the second portionalong the path to resist sliding; rotating the second portion away fromthe first portion so that the elongate medical instrument abuts thefirst portion and is free of the second portion. The first and secondportions may be rotatable with respect to each other using one hand of auser. Also, the second portion may be rotated with respect to the firstportion without substantial movement of the elongate medical instrumentaway from the first portion. The cavity may define a central axis, andwherein the second portion may be rotatable with respect to the firstportion without substantial movement of the elongate medical instrumentaway from the central axis.

The invention additionally relates to an instrument guide including asecuring portion for securing the instrument guide to an imagingtransducer and an instrument engaging portion for operatively securingan instrument to the instrument guide along a guide path. At least afirst portion of the instrument engaging portion may be rotatablyadjustable with respect to the securing portion to allow correspondingrotational adjustment of the guide path with respect to the securingportion. The instrument may be a biopsy needle or a cryoprobe. Theinstrument may be configured to aspirate a material, heat or cool atissue, emit microwaves, or emit radio waves. Also the instrument may beconfigured to introduce a substance to a tissue, wherein the substancemay include ethanol. The instrument guide may permit capture and releasein an imaging plane. The instrument guide also may include avernier-type mechanism for exerting a user-adjustable “drag” on aninstrument in the guide.

Preferred embodiments of instrument guides of the present invention maybe operatively secured to an ultrasound transducer that may function inan in-plane relationship to an imaging plane. Such instrument guidesalso may have a single cavity for engaging multiple different needlediameters without the requirement for additional parts or attachments. Areciprocating mechanism may be provided for securely engaging,accurately guiding, and quickly releasing an instrument such as aneedle, probe or catheter in an imaging plane. The angle of approach inthe chosen image plane may be adjusted by an operator before or during aprocedure, and may be fixed as desired. Frictional resistance of theinstrument to sliding motion through the guide also may beoperator-adjustable. The guides may be made of a variety of materialsthat may be selected for their appropriateness in disposable or reusableguides.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred features of the present invention are disclosed in theaccompanying drawings, wherein:

FIG. 1 shows an exploded perspective view of an embodiment of a medicalinstrument guide according to the present invention;

FIG. 2 shows the guide body of FIG. 1, including (2 a) a sideperspective view, (2 b) a bottom view, (2 c) a top view, (2 d) a sideview, (2 e) another side view, (2 f) a front view, and (2 g) a backview;

FIG. 3 shows the quick-release lever of FIG. 1, including (3 a) a sideperspective view, (3 b) a bottom view, (3 c) a top view, (3 d) a sideview, (3 e) another side view, (3 f) a front view, and (3 g) a backview;

FIG. 4 shows the lock of FIG. 1, including (4 a) a side perspectiveview, (4 b) a bottom view, (4 c) a top view, (4 d) a side view, (4 e)another side view, (4 f) a front view, and (4 g) a back view;

FIG. 5 shows an embodiment of a bracket according to the presentinvention for demountable attachment to the guide body of FIG. 1,including (5 a) a side perspective view, (5 b) a bottom view, (5 c) atop view, (5 d) a side view, (5 e) another side view, (5 f) a frontview, and (5 g) a back view;

FIG. 6 shows a first embodiment of an insert according to the presentinvention, including (6 a) a side perspective view, (6 b) a bottom view,(6 c) a top view, (6 d) a side view, (6 e) another side view, (6 f) afront view, and (6 g) a back view;

FIG. 7 shows a second embodiment of an insert according to the presentinvention, including (7 a) a side perspective view, (7 b) a bottom view,(7 c) a top view, (7 d) a side view, (7 e) another side view, (7 f) afront view, and (7 g) a back view;

FIGS. 8 a and 8 b show perspective views of the guide of FIG. 1 with aninsert being coupled thereto;

FIGS. 9 a and 9 b show perspective views of the insert of FIG. 8 beingpositioned at different index positions corresponding to differentgauges accommodated by the instrument-receiving channel of the guide ofFIG. 1;

FIG. 10 shows a top perspective view of the guide of FIG. 1 with aninsert disengaged from the guide body;

FIG. 11 shows a side perspective view of the guide of FIG. 1 with abracket coupled thereto and an insert engaged with the guide body;

FIG. 12 shows a top view of the guide of FIG. 1 with an insert engagedwith the guide body to form an instrument-receiving channel of a firstsize;

FIG. 13 shows another top view of the guide of FIG. 1 with an insertengaged with the guide body to form an instrument-receiving channel of asecond size;

FIGS. 14 a and 14 b schematically demonstrate the operation principlebehind a preferred exemplary embodiment of the selectable sizeinstrument-receiving channel;

FIG. 15 shows another embodiment of a medical instrument guide accordingto the present invention, including (15 a) a first side perspectiveview, (15 b) a second side perspective view, (15 c) a third sideperspective view, and (15 d) a fourth side perspective view; and

FIG. 16 shows yet another embodiment of a medical instrument guideaccording to the present invention, including (16 a) a first sideperspective view and (16 b) a second side perspective view.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Terms such as “upper,” “lower,” “front” and “back” as used herein areprovided as a non-limiting examples of the orientation of features.

Referring initially to FIG. 1, a medical instrument guide according toone exemplary embodiment of the present invention is shown. Medicalinstrument guide 10 includes a guide body 12, a quick-release lever 14,an insert 16, and a lock 18. As will be described in detail below, guidebody 12 and insert 16 are configured and dimensioned to cooperate toform an instrument-receiving channel.

Turning to FIG. 2, guide body 12 includes supports 14, 16 definingrespective support surfaces 18, 20 upon which an elongate medicalinstrument such as a needle will abut. In the preferred exemplaryembodiment, support surfaces 18, 20 are disposed at about 90° withrespect to each other. In alternate embodiments, these surfaces may beat a different angle so long as they are disposed transverse to oneanother. Guide body 12 preferably has an upper end 12 a and a lower end12 b. Proximate upper end 12 a, an inwardly curvate, tapering lip 21 maybridge support surfaces 18, 20 for use in guiding a member along thesesurfaces. A guide groove 18 a extends in support surface 18 transverseto support surface 20. In addition, a shoulder 20 a protrudes proximateupper end 12 a of support surface 20, while a recess or notch 20 b isdisposed proximate lower end 12 b of support surface 20.

A securing region 22 is provided for attaching guide 10 for example toan imaging instrument, as will be described shortly. In one preferredexemplary embodiment as shown in FIG. 2, securing region 22 isconfigured and dimensioned as a channel. Also, a first protrusion 24 isprovided within securing region 22 for permitting a releasablemechanical interlock with an object inserted in securing region 22. Forexample, if a portion of a bracket for supporting an imaging instrumentis inserted in securing region 22, protrusion 24 may be received in alike-shaped groove therein.

The preferred exemplary embodiment of guide body 12 includes a couplingregion 26 that may be configured as a generally cylindrical channel orsocket for providing a pivotable connection with a suitably shapedmember. Preferably coupling region 26 is disposed closer upper end 12 athan lower end 12 b. In the preferred embodiment, coupling region 26 isdisposed proximate upper end 12 a.

Guide body 12 further includes a lock indexing section 28 with arcuateguide surface 29 and indexing positions 30. In one preferred exemplaryembodiment, section 28 includes a front surfaces 28 a that providessufficient surface area for accommodating a portion of a user's fingersuch as the fleshy tip of a user's thumb or index finger. Lock indexingsection 28 is provided to be operably associated with lock 18. Ashoulder 32 is provided on a back side of guide body 12, and a cutout 34is included for accommodating a portion of lock 18, as will bedescribed.

Referring next to FIG. 3, quick-release lever 14 is shown including asupport portion 40, a gauge-indicator portion 42, and a detent 44.Quick-release lever 14 preferably has an upper end 14 a and a lower end14 b. Similar to guide body 12, one preferred exemplary embodiment ofsupport portion 40 includes a front surface 40 a that providessufficient surface area for accommodating a portion of a user's fingersuch as the fleshy tip of a user's thumb or index finger. A back surface40 b with raised wall 41 provides further sufficient surface area foraccommodating a portion of a user's other finger such as the fleshy tipof a user's thumb or index finger. Thus, support portion 40 may begrasped between two fingers each resting on a surface 40 a, 40 b, withraised wall 41 providing additional leverage.

In addition, gauge-indicator portion 42 protrudes from a support surface46 and preferably is generally disposed about halfway across a widththereof. Portion 42 preferably is disposed closer lower end 14 b thanupper end 14 a. In the preferred exemplary embodiment, portion 42extends from about midway between upper and lower ends 14 a, 14 b,respectively, to proximate lower end 14 b. A nub 42 a extends outwardfrom an end of gauge-indicator portion 42.

Rails 48 a, 48 b preferably are positioned on opposing sides of supportsurface 46 for receiving insert 16, as will be described. A pivot member50 preferably is provided proximate upper end 14 a, and in the preferredexemplary embodiment is generally cylindrical and is configured anddimensioned for demountable snap-fitting and pivoting in socket 26.

Detent 44 preferably extends toward gauge-indicator portion 42 and isaligned with nub 42 a thereof. In a preferred exemplary embodiment,detent 44 has a generally triangular tip as shown for example in FIGS. 3f and 3 g.

Windows 52, 54 optionally may be provided in gauge-indicator portion 42.The cut-out 52 permits inspection of pivot member 50, particularly whenpivotably associated with socket 26 of guide body 12, and also permitssocket 26 to articulate therein. Cut-out 54 permits visualization behindgauge-indicator portion 42 and concomitantly provides a contrastingfield of view when inspecting detent 44.

A recess or ledge 56 a also is provided proximate upper end 14 a along aside surface 57 of gauge-indicator portion 42. Ledge 56 a is configuredand dimensioned to receive shoulder 20 a of guide body 12 when pivotmember 50 is pivotably associated with socket 26. Additionally, ashoulder 56 b is provided proximate lower end 14 b along side surface57, and is configured and dimensioned to be received in notch 20 b ofguide body 12 when pivot member 50 is pivotably associated with socket26. In an alternate embodiment, however, each of guide body 12 andgauge-indicator portion 42 may be provided with one or more shoulders orone or more mating recesses for facilitating coupling and alignment ofguide body 12 with respect to gauge-indicator portion 42.

Turning now to FIG. 4, lock 18 will be described. A lever 60 is providedfor demountable and pivotable attachment to guide body 12 and which isoperable between unlocked and locked, indexed positions thereon. Lever60 includes side surfaces 60 a, 60 b, 60 c adjacent but transverselyoriented each other, as well as opposed side surface 60 d. Sidesurfaces, 60 a, 60 b, 60 c together and side surface 60 d providesufficient surface area for accommodating a portion of a user's fingersuch as the fleshy tip of a user's thumb or index finger. Thus, locklever 60 may be grasped between two fingers each resting on eithersurfaces 60 a, 60 b or on surface 60 c. Lock 18 further includes a backsurface 62 with raised wall 63 that provides further sufficient surfacearea for accommodating a portion of a user's other finger such as thefleshy tip of a user's thumb or index finger. When lock 18 isdemountably coupled to guide body 12, the assembled lock 18 and guidebody 12 may be grasped between two fingers each resting on a surface 62,28 a, respectively, with raised wall 63 providing additional leverage.

A post 64 extends from a front surface 65 of lock 18, preferablygenerally perpendicular thereto. Post 64 is provided for pivoting inarcuate guide surface 29 of guide body 12. Lock 18 is configured anddimensioned such that when post 64 abuts arcuate guide surface 29,finger 66 of lock 18 indexes with lock indexing section 28 of guide body12. In a preferred exemplary embodiment, lever 60 is provided at anupper end 68 a of lock 18, while post 64 is provided at a lower end 68b.

A second protrusion 70 extends from a side of lock 18, and ispositioned, configured and dimensioned such that when post 64 is seatedagainst arcuate guide surface 29 and finger 66 indexes with lockindexing section 28 of guide body 12, protrusion 70 may be selectivelydisposed to oppose first protrusion 24 of guide body 12 and extendwithin securing region 22. In combination, first and second protrusions24, 70 thus permit a releasable mechanical interlock with an objectinserted in securing region 22, as previously discussed. Secondprotrusion may be disposed in a retracted position within cutout 34 ofshoulder 32 of guide body 12 corresponding to the unlocked indexedposition of lock 18, or may be disposed in an extended position beyondcutout 34 of shoulder 32 and within securing region 22 corresponding tothe locked indexed position of lock 18. Thus, for example, if a portionof a bracket for supporting an imaging instrument is inserted insecuring region 22, protrusions 24, 70 may be received in like-shapedgrooves therein.

A preferred exemplar bracket 80 for supporting an imaging instrument andfor coupling to guide 10 is shown in FIG. 5. Bracket 80 includes animaging instrument receiving opening 82 framed by support walls 83, anda coupling section 84 for connecting to guide 10. Grooves 86, 88 aredisposed on opposing sides of coupling section 84, so that when bracket80 is connected to guide 10, protrusions 24, 70 of guide body 12 andlock 18, respectively, may be received in and mate with like-shapedgrooves 86, 88 to releasably secure coupling section 84 to guide 10. Ascan be seen for example in FIGS. 5 d and 5 e, support walls 83 arecurvate. Preferably, bracket 80 is configured and dimensioned such thatwhen guide 10 is coupled thereto and an imaging instrument is disposedin receiving opening 82, an instrument received in theinstrument-receiving channel of guide 10 is aligned or readily alignablewith the imaging instrument.

Turning to FIGS. 6 and 7, first and second inserts 16, 110 according tothe present invention are shown. In the preferred exemplary embodiment,each insert is configured for selecting an instrument-receiving channelsized to accommodate each of five different gauge sizes. In alternateembodiments, however, each insert may be sized to accommodate any numberof different gauge sizes, from a single gauge size to a plurality ofgauge sizes. Exemplary insert 16 is configured for use with gauge sizes16, 17, 18, 20 and 22, while exemplary insert 110 is configured for usewith gauge sizes 11, 12, 13, 14 and 15. However, other gauge sizes maybe provided to suit a particular need.

Because guide 10 may be used, for example, with needles and catheters,the sizes of these devices are correlated in Tables 1 and 2 forreference. Needles are typically measured by Birmingham or Stubs' gauge,so that the larger the gauge number, the smaller the needle outsidediameter. Catheters are measured in French (Fr.) size, so that 3 Fr. isequal to 1 millimeter in outside diameter. Thus, even though inserts 16,110 are provided with indicia 90, 112 indicating gauge size, otherindicia may be provided instead or in addition to indicate dimensions inmillimeters, inches, or French size.

TABLE 1 Gauge Outer Dia. Outer Dia. No. (in.) (mm) 10 0.134 3.40 110.120 3.05 12 0.109 2.77 13 0.095 2.41 14 0.083 2.11 15 0.072 1.83 160.065 1.65 17 0.058 1.47 18 0.049 1.24 19 0.042 1.07 20 0.035 0.89 210.032 0.81 22 0.028 0.71 23 0.025 0.64 24 0.022 0.56 25 0.020 0.51

TABLE 2 Size Outer Dia. Outer Dia. (Fr.) (in.) (mm) 3 0.039 1.00 4 0.0531.33 5 0.066 1.67 6 0.079 2.00 7 0.092 2.33 8 0.105 2.67 9 0.118 3.00 100.131 3.33 11 0.144 3.67 12 0.158 4.00 13 0.170 4.33 14 0.184 4.67 150.197 5.00 16 0.210 5.33 17 0.223 5.67 18 0.236 6.00

First and second inserts 16, 110 are similar in design, and thus onlyfirst insert 16 will be described in detail herein. However, thefeatures described for insert 16 are likewise descriptive of the designof insert 110. Insert 16 preferably has an upper end 92 and a lower end94. Proximate ends 92, 94 are disposed respective supports 96, 98 thateach provide sufficient surface area 100, 102 for accommodating aportion of a user's finger such as the fleshy tip of a user's thumb orindex finger. Thus, insert 16 may be grasped between two fingers eachresting on a surface 100, 102, for positioning of insert 16 onquick-release lever 14 and for selective movement of insert 16 thereon.

Insert 16 is provided with a plurality of notches 104 shaped forselective engagement with detent 44 of quick-release lever 14, thusproviding a plurality of discrete stops. Each notch 104 corresponds toone of the gauge sizes also indicated by indicia 90. Additional indicia106, as for example shown in FIG. 6 f, correspond to each notch 104 anda particular gauge size. A central slot 108 is configured anddimensioned for receiving gauge-indicator portion 42 of quick-releaselever 14 and nub 42 a thereof when insert 16 is coupled to quick-releaselever 14. End 108 a of slot 108 serves as a stop for limiting travel ofinsert 16 when nub 42 a of gauge-indicator portion 42 of quick-releaselever 14 abuts end 108 a.

Grooves 110, 112 are provided on a back side 114 of insert 16 foroperable association with rails 48 a, 48 b of quick-release lever 14.Thus, rails 48 a, 48 b ride along grooves 110, 112 to guide the movementof insert 16. Preferably, grooves 110, 112 are parallel, and rails 48 a,48 b also are parallel so that they all may be aligned with respect toeach other for movement. FIG. 6 d shows a first side of insert 16 havinga generally triangular profile. Grooves 110, 112 preferably are disposedgenerally transverse to lower edge 116 but generally parallel to upperedges 118 and/or 120.

In addition, insert 16 includes a locking portion 122 for releasableengagement with guide groove 18 a in guide body 12. Locking portion 122is disposed about halfway between upper and lower ends 92, 94 on a sideopposite of guide body 10 opposite notches 104. In some embodiments,locking portion 122 may include a raised portion 122 a and a lowerportion 122 b to facilitate engagement with guide groove 18 a.

An elongate support 124 with a support surface 124 a is provided for usein guiding a member therealong, and serves this purpose preferably incombination with support surfaces 18, 20 of guide body 12. In theexemplary preferred embodiment, support 124 extends the entire length ofinsert 16 and is disposed on the same side as locking portion 122.Proximate upper end 92, an inwardly curvate, tapering lip 126 isdisposed for use in guiding a member along support surface 124 a. Thecombination of tapering lip 126 with tapering lip 21 bridging supportsurfaces 18, 20 of guide body 12 creates a funnel-style insertion pointthat for example, facilitates quick instrument placement in darkenedultrasound suites.

With each of the components of guide 10 now described, next theoperation of guide 10 is explained. A user may select an appropriateinsert 16, 110 according to the size instrument to be used with guide10. For example, if a user desires to guide an 18 gauge needle usingguide 10, then insert 16 is appropriate, whereas for a 12 gauge needleinsert 110 may be used. As shown in FIG. 8, guide 10 is disposed in anopen position. Insert 16 may be installed on quick-release lever 14 bymoving insert 16 in the direction of arrow A, as shown in FIG. 8 a, sothat grooves 110, 112 slide along rails 48 a, 48 b of quick-releaselever 14, as previously described. Preferably, insert 16 may only bedemountably attached to quick-release lever 14 when guide 10 is disposedin the open position with guide body 12 pivoted away from quick-releaselever 14, as shown with arrow B. As shown in FIG. 8 b, when insert 16 iscoupled to quick-release lever 14, detent 44 may be indexed to a notch104 to select the desired gauge, in a ratchet-like relationship. Also,gauge-indicator portion 42 and nub 42 a of quick-release lever 14 aredisposed coaxially with central slot 108 and received therein.

As can be seen in FIG. 9, when a particular gauge is selected, detent 44indexes with a notch 104 corresponding to numerical and associatedindicia 90, 106, with nub 42 a generally aligned with indicia 90, 106.Thus, a user has several indicators that confirm the selection of aparticular gauge size. Also shown in FIG. 9, lock 18 is shown disengagedentirely from arcuate guide surface 29 of lock indexing section 28, forclarification purposes only. In use, finger 66 of lock 18 would beengaged with lock indexing section 28 of guide body 12, and would bemoveable in the direction of arrow C as shown. To demonstrate theselection of an alternate gauge size permitted by insert 16, FIG. 9 bshows the positioning of insert 16 on quick-release lever 14 so that 22gauge is selected.

Another perspective view of guide 10 is shown in FIG. 10. As can beseen, finger 66 of lock 18 may be engaged with lock indexing section 28of guide body 12 in a first recess 130 corresponding to unlockedposition of lock 18, or in a second recess 132 corresponding to a lockedposition of lock 18 as previously described.

Guide body 12 and quick-release lever 14 are rotatably associated witheach other and may be pivoted in the direction of arrow B. When rotatedso that locking portion 122 of insert 16 engages guide groove 18 a ofguide body 12, the instrument-receiving channel of guide 10 is formed.

Yet another perspective view of guide 10 is shown in FIG. 11, with aninstrument-receiving channel 140 formed for receiving an instrument 142(shown in phantom) therein. Bracket 80 is shown demountably attached toguide body 12.

Turning to FIGS. 12 and 13, two views of guide 10 are shown with insert16 disposed in different positions thus selecting different gauge sizes.As can be seen in FIG. 12, instrument-receiving channel 140 has a firstsize, while in FIG. 13 the instrument-receiving channel 140 has a secondsize smaller than the first size. This suggests that guide 10 is set inFIG. 12 to accommodate a smaller gauge (and hence larger outer diameter)instrument than in FIG. 13. Also, second protrusion 70 of lock 18 isshown in the completely disengaged position, as well as shown in phantomwhere indicating where it would be disposed when finger 66 of lock 18 isdisposed in second recess 132 of lock indexing section 28 of guide body12, corresponding to a locked position of lock 18

The operation principle behind a preferred exemplary embodiment of theselectable size instrument-receiving channel 140 is clarified in FIGS.14 a and 14 b, which show a simplified representation of the mechanismused to change the size of this path. In these simplified drawings, twosizes of instrument-receiving channel 140 are shown as distances A andA′, respectively, while two distances of insert 16 along rails 48 a, 48b of quick-release lever 14 are shown as B and B′, respectively. Asevident from the figures, when insert 16 travels toward lower end 12 bof guide body 12, A′<A and B′<B thereby creating a more narrowinstrument-receiving channel 140. In the preferred exemplary embodiment,insert 16 travels along rails 48 a, 48 b at an angle α that is about 45degrees or less. Therefore, the distance moved along the inserts pathcorresponds to a shorter distance change in the “diameter” or size ofthe needle path. In this manner, relatively fine adjustments in theneedle path diameter can be made. Also, in the preferred exemplaryembodiment, a plurality of central axes are definable ininstrument-receiving channel 140 due to the movable insert, preferablywith each of the central axes being parallel to one another.

As disclosed herein, the bracket 80 and guide 10 may provide users suchas physicians with a tool for performing needle-guided or catheterprocedures with the use of ultrasound transducers. As known in the art,during use, a transducer may first be disposed in a transducer cover.The cover preferably is installed with an appropriate amount of gel orother lubricating agent inside the cover and/or on the transducer face.The cover is pulled tightly over the transducer face to remove wrinklesand air bubbles, taking care to avoid puncturing the cover. The covermay be secured to the transducer with elastic bands or other means. Anappropriate insert 16 is selected based on the gauge size required, andthe insert 16 is slidably placed on the quick-release lever 14. Thedesired gauge size indicia 90, 106 are aligned with the detent 44 andnub 42 a, and the quick-release lever 14 is snapped closed with theinsert 16 engaging the guide body 12. The instrument-receiving channel140 is then formed. Using a proper sterile technique, the unlocked guidebody 12 is then coupled to a bracket 80, and lock 18 is moves into thelocked position so that guide body 12 is releasably secured to bracket80. The gauge selection may then be verified. Of course, instrument pathverification also should be performed to verify that the desired pathhas been selected. For example, for a guide 10 attached to an ultrasoundprobe, a needle disposed in the instrument-receiving channel of theguide should remain in the imaging plane. Guide 10 permits such a needleto both be captured in the imaging pane and released from guide 10 whileremaining in the imaging plane. An appropriate instrument length shouldbe selected.

Advantageously, insert 16 may be adjusted once an instrument has beenplaced in instrument-receiving channel 140 so that a desired feel may beachieved. In addition, in the preferred exemplary embodiment,quick-release lever 14 advantageously permits an instrument guided andcaptured within instrument-receiving channel 140 to be easily releasedtherefrom by applying downward pressure on front surface 40 a of supportportion 40. Thus, the guide 10 can be “popped” open to easily release aninstrument therefrom, and advantageously the instrument may be releasedwithout the instrument twisting or rotating in channel 140. Only onehand of the user may be required to manually manipulate guide 10 torelease the instrument. Also in the preferred exemplary embodiment,because of the pivotable coupling of the guide body 12 and quick-releaselever 14, when these components are in an open position an instrumentsuch as a needle may be inserted or removed sideways from guide 10(e.g., in a direction along support surface 20 of guide body 12 towardquick-release lever 14). An enhanced visual field is also provided ascompared to prior art guides requiring instruments to be removed axiallyalong the instrument-receiving channel thereof.

Advantageously, guide 10 may provide an instrument-receiving channel 140that has minimal drag when an instrument is disposed therein. Because ofthe low drag, a user may have enhanced “feel” when positioning aninstrument with guide 10 for example during a biopsy procedure.Moreover, guide 10 permits interchangeable inserts to be used so thatmany different gauges of instruments may be accommodated. Further,instead of only one gauge size being accommodated per insert, theinserts 16, 110 of the present invention each accommodate selection ofmultiple gauge sizes. Whereas prior art needle guides required teninserts corresponding to ten different gauge sizes, the presentinvention for example provides only two inserts that together correspondto ten different gauge sizes. Thus, a wide range of gauge adjustment ispossible with a single insert 16, 110, and the number of components tobe supplied to the physician may be smaller thereby permitting increasesin efficiency and cost-effectiveness. In addition, guide 10 providesergonomically advantageous features to enhance ease of use, such asregions for manipulating guide 10 with only one or two fingers.

In addition, guide 10 may permit enhanced functionality and control overfixed-angle devices by permitting selection of multiple angles.Optionally, the needle guide may permit placement of more than oneneedle into a patient at one time, or facilitate multiple placements.

Guide 10 is applicable, for example, in abdominal fine needleaspiration, core biopsy, drainage aspiration, amniocentesis, andcatheterization procedures.

Guide 10 may be a single-use, disposable system. Preferably, thecomponents of guide 10 described herein may be formed ofinjection-molded, ABS polymer. To assist users, each of the componentsmay be color-coded.

Turning to FIGS. 15 and 16, additional exemplary embodiments ofinstrument guides are shown. Referring first to FIG. 15, a needle guide210 may include a securing portion 212 and an instrument engagingportion 214. Securing portion 212 is preferably configured to releasablysecure needle guide 210 to an imaging transducer. Securing portion 212may comprise an open clip 215 having first and second ends 216, 218. Anangle θ between a line 220 connecting first and second ends 216, 218 andan instrument guide path 222 of instrument engaging portion 214 ispreferably less that 45°, for example less than 20°. In one exemplaryembodiment, line 220 and guide path 222 are aligned with one another. Inone exemplary embodiment, line 220 and guide path 222 are containedwithin a single plane.

Instrument engaging portion 214 is preferably configured to operativelysecure an instrument, such as a biopsy needle, along guide path 222.Engaging portion 214 may comprise first and second engaging portions224, 226. First engaging portion 224 may include at least one surface228 preferably shaped to accommodate a portion of an instrument. Firstengaging portion 224 may include a second surface 229 spaced part alongthe guide path 222 from surface 228 and preferably shaped to accommodatea portion of the instrument. Second engaging portion 226 preferablyincludes a surface 230 also preferably shaped to accommodate a portionof the instrument. First and second engaging portions 224, 226 maycooperate to operatively secure the instrument. For example, aninstrument may be compressed between (a) surface 230 and (b) surface 228and, optionally, surface 229. In one exemplary embodiment, surfaces228-230 contact the instrument in a three-point contact configuration.Preferably, the first and second portions 224, 226 are configured toreceive an instrument laterally with respect to the guide path 222. Aresilient member or compression spring 239 a may be provided to biassecond engaging portion 226. This spring-loaded arrangement preferablyis configured so that movement of second engaging portion 226 in adirection parallel to a central axis of thumb screw 239 b is resisted,and thus second engaging portion 226 may releasably abut and retain aninstrument along guide path 222. A finger depression surface 239 c maybe provided so that pressure applied on surface 239 c toward thumb screw239 b may release an instrument captured along guide path 222.

Engaging portion 214 may be configured to allow motion, for examplerotation, of guide path 222. Preferably, guide path 222 may be rotatedwith respect to securing portion 212. In one embodiment, a rotationalmotion of guide path 222 is accompanied by a rotational motion of atleast one of first and second engaging portions 224, 226 so that anorientation of guide path 222 relative to the first and second engagingportions 224, 226 does not change as guide path 222 is rotated. Anexample of this may be seen upon comparing FIGS. 15 a and 15 d. Anarcuate ratcheting mechanism 240 may be provided for angular adjustmentand retention of securing portion 212 in pre-set angular positions withrespect to engaging portion 214, with securing portion 212 beingpivotally connected to engaging portion 214 along axis 242. A pin 241 aof portion 214, for example, may be received in a plurality of grooves241 b formed in ratcheting mechanism 240 of portion 212. Thumb screw 239b is provided to apply selectable pressure against an instrument heldalong axis 242 and thus provides selectable drag on the instrument.

Referring to FIG. 16, yet another embodiment of an instrument guide 210′is shown and may include a securing portion 212′ and an instrumentengaging portion 214′. Labeled elements of FIG. 16 having similarreference numerals with elements of FIG. 15 and thus may have similarfunctions with those elements. In particular, a needle guide 210′ mayinclude a securing portion 212′ and an instrument engaging portion 214′.Securing portion 212′ preferably may be configured for use with abracket to releasably secure needle guide 210′, for example, to animaging transducer. Securing portion 212′ may comprise first and secondends 216′, 218′. In one exemplary embodiment, an angle between a line220′ connecting first and second ends 216′, 218′ and an instrument guidepath 222′ of instrument engaging portion 214′ is preferably less that45°, for example less than 20°. Also in one exemplary embodiment, line220′ and guide path 222′ may be aligned with one another. Further, inone exemplary embodiment, line 220′ and guide path 222′ are containedwithin a single plane.

Instrument engaging portion 214′ is preferably configured to operativelysecure an instrument, such as a biopsy needle, along guide path 222′.Engaging portion 214′ may comprise first and second engaging portions224′, 226′. First engaging portion 224′ may include at least one surface228′ preferably shaped to accommodate a portion of an instrument. Firstengaging portion 224′ may include a second surface 229′ spaced partalong the guide path 222′ from surface 228′ and preferably shaped toaccommodate a portion of the instrument. Second engaging portion 226′preferably includes a surface 230′ also preferably shaped to accommodatea portion of the instrument. First and second engaging portions 224′,226′ may cooperate to operatively secure the instrument, for example byforming an instrument receiving chamber. For example, an instrument maybe compressed between (a) surface 230′ and (b) surface 228′ and,optionally, surface 229′. In one exemplary embodiment, surfaces228′-230′ contact the instrument in a three-point contact configuration.Preferably, the first and second portions 224′, 226′ are configured toreceive an instrument laterally with respect to the guide path 222′. Aresilient member or torsion spring 239 a′ may be provided to bias secondengaging portion 226′, which rotates about axis 250 in direction C,toward a position that abuts an instrument releasably retained alongguide path 222′. A finger depression surface 239 c′ may be provided sothat pressure applied on surface 239 c′ may release or capture aninstrument, as desired, along guide path 222.

Engaging portion 214′ may be configured to allow motion, for examplerotation, of guide path 222′. Preferably, guide path 222′ may be rotatedwith respect to securing portion 212′. In one embodiment, a rotationalmotion of guide path 222′ is accompanied by a rotational motion of atleast one of first and second engaging portions 224′, 226′ so that anorientation of guide path 222′ relative to the first and second engagingportions 224′, 226′ does not change as guide path 222′ is rotated. Anarcuate ratcheting mechanism 240′ may be provided for angular adjustmentand retention of securing portion 212′ in pre-set angular positions withrespect to engaging portion 214′, with securing portion 212′ beingpivotally connected to engaging portion 214′ along axis 242′. Aprotrusion 241 a′ of portion 214′, for example, may be received in aplurality of grooves 241 b′ formed in ratcheting mechanism 240′ ofportion 212′. Thumb screw 239 b′ is provided to apply selectablepressure on surface 239 c′ and consequently selectable pressure ofsurface 230′ against an instrument held along axis 242′. Thus,adjustment knob 239 b′ may provide selectable drag on the instrument.

Advantageously, instrument guides 210, 210′ may offer features directedto the benefits of the freehand method while also having the inherentlygreater control and security of the needle guide method (as thesemethods were described above). In preferred exemplary embodiments,instrument guides 210, 210′ may accept any instrument such as a needle,probe or catheter having a diameter including but not limited to all ofthe standard sizes of 27 gauge through 8.5 French. Preferably, quickengagement or disengagement of a guide 210, 210′ with an instrument maybe effected by pressure applied by a finger, while maintaining view ofthe instrument in the image plane. Also, advantageously the angle ofattack for the instrument in the image plane may be user selectable overan angular range by virtue of the arcuate ratcheting mechanisms 240,240′ that also may maintain the chosen angle. In addition, the “deadspace” problem may be eliminated by virtue of a curved shoe 252 at thebase of the guide. Preferred exemplary embodiments of instrument guides210, 210′ are formed of single use, injection molded parts whose designand related manufacturing costs allow the guides to be cost effectivefor use.

While various descriptions of the present invention are described above,it should be understood that the various features can be used singly orin any combination thereof. Therefore, this invention is not to belimited to only the specifically preferred embodiments depicted herein.

Further, it should be understood that variations and modificationswithin the spirit and scope of the invention may occur to those skilledin the art to which the invention pertains. For example, guide body 12and quick-release lever 14 may be formed of unitary construction, with aflexible portion disposed therebetween to permit opening and closing ofthe device to form instrument-receiving channel 140. Accordingly, allexpedient modifications readily attainable by one versed in the art fromthe disclosure set forth herein that are within the scope and spirit ofthe present invention are to be included as further embodiments of thepresent invention. The scope of the present invention is accordinglydefined as set forth in the appended claims.

What is claimed is:
 1. An instrument guide system for use with anultrasound transducer and a sterile cover to provide a plurality ofdifferent angled guide paths for an instrument to penetrate into thebody of a patient, said instrument guide system comprising a bracket andan instrument guide, said bracket being arranged for releasable mountingon the ultrasound transducer, said instrument guide comprising a clipincluding a pair of ends arranged to snap fit to associated portions ofsaid bracket to releasably secure said instrument guide to said bracketwith said sterile cover interposed therebetween, said instrument guidecomprising a first engaging surface and a second engaging surface, saidsurfaces being spring biased to be movable with respect to each other toform a channel of adjustable width therebetween, said channel beingarranged to receive selected portions of respective instruments therein,which selected portions are of different gauges, said channel also beingadjustable in orientation with respect to said bracket to establish aselected one of said plurality of different guide paths for theinstrument, whereupon when the instrument is received in said channel ofsaid instrument guide in any selected one of said guide paths it can beused to penetrate into the body of a patient to the desired depth. 2.The instrument guide system of claim 1 wherein said openable channel ofsaid instrument guide enables the ultrasound transducer and theinstrument guide system to be removed from the instrument while leavingthe instrument in place penetrating into the body of the patient.
 3. Theinstrument guide system of claim 2 wherein said instrument guidecomprises a pivotable member arranged for establishing the pluraldiscrete guide paths desired for the instrument.
 4. The instrument guidesystem of claim 1 wherein said channel comprises a first engagingportion and a second engaging portion which are movable relative to eachother capture the instrument therebetween in said selected one of saidguide paths.
 5. The instrument guide system of claim 4 wherein saidsecond engaging portion is biased toward said first engaging portion tocapture the instrument therebetween.
 6. The instrument guide system ofclaim 5 additionally comprising a member coupled to said second engagingportion and arranged to be pressed by a user to enable the capturedinstrument to be released so that said instrument guide and theultrasound transducer can be removed from the instrument.
 7. Theinstrument guide system of claim 1 wherein said instrument guidecomprises a pivotable member arranged for establishing the pluraldiscrete guide paths desired for the instrument.
 8. The instrument guideof claim 7 wherein one of said ends of said clip includes a projectionand the other of said ends comprises a pin-like member.
 9. Theinstrument guide of claim 1 wherein one of said ends of said clipincludes a projection and the other of said ends comprises a pin-likemember.
 10. An instrument guide system for use with an ultrasoundtransducer and a sterile cover to provide a plurality of different,discrete angled guide paths for an instrument to be introduced into thebody of a patient, said instrument guide system comprising a bracket andan instrument guide, said bracket being arranged for releasable mountingon the ultrasound transducer, said instrument guide comprising a firstengaging surface and a second engaging surface, said surfaces beingspring biased to be movable with respect to each other to form a channelof adjustable width therebetween, said channel being arranged to receiveselected portions of respective instruments therein, which selectedportions are of different gauges, said instrument guide being arrangedto be releasably attached to said bracket to establish a selected one ofsaid plurality of different discrete guide paths for a receipt of theinstrument, whereupon when the instrument is received in said channel inany selected one of said guide paths it can be used to penetrate intothe body of a patient to the desired depth, said channel being openableto enable the ultrasound transducer and the instrument guide system tobe removed from the instrument while leaving the instrument in placepenetrating into the body of the patient.
 11. The instrument guidesystem of claim 10 wherein said instrument guide comprises a clip forreleasably securing said instrument guide to said bracket.
 12. Theinstrument guide system of claim 10 additionally comprising a membercoupled to said second engaging surface and arranged to be pressed by auser to enable the portion of the instrument received within saidchannel to be released so that said instrument guide and the ultrasoundtransducer can be removed from the instrument.
 13. The instrument guidesystem of claim 10 wherein said instrument guide comprises a pivotablemember arranged for establishing the plural discrete paths desired forthe instrument.
 14. The instrument guide system of claim 10 wherein theultrasound transducer is disposed within the sterile cover and whereinsaid instrument guide is arranged to be releasably secured to saidbracket with the sterile cover interposed therebetween.